EFFECTS OF LANDAU DAMPING ON NONLINEAR WAVE MODULATION IN PLASMA.

On the basis of the Vlasov equation, an equation to describe behaviour of the electric potential is obtained for small but finite amplitude waves in a plasma. Under a certain stretching scheme, the equation is reduced to the generalized nonlinear Schrodinger equation \(i\frac{\partial\psi}{\partial\zeta}+\alpha\frac{\partial^{2}\psi}{\partial\eta^{2}}+\beta|\psi|^{2}\psi+i\gamma\psi{=}0\), where α and β are constants (αβ<0) and γ means the damping constant. The decay process of the nonlinear electron plasma wave is investigated on the basis of this equation. It is found that the soliton can exist for finite time interval, and under a certain condition the amplitude of soliton grows first and then damps away.